feat: add iglesia-light and comic-relief fonts; add gnome.gnome-font-viewer

overlays/fonts/iglesia-light.nix

@@ -0,0 +1,18 @@
+{ pkgs }: pkgs.stdenv.mkDerivation {
+  pname = "iglesia-light-typeface";
+  version = "1.009";
+
+  src = ./iglesia-light.zip;
+
+  unpackPhase = ''
+    runHook preUnpack
+    ${pkgs.unzip}/bin/unzip $src
+    runHook postUnpack
+  '';
+
+  installPhase = ''
+    runHook preInstall
+    install -Dm644 Iglesia\ Light.ttf -t $out/share/fonts/truetype
+    runHook postInstall
+  '';
+}